The Collaborative International Dictionary of English v.0.48:

Fertile \Fer"tile\ (? or ?; 277), a. [L. fertilis, fr. ferre to
   bear, produce: cf. F. fertile. See Bear to support.]
   1. Producing fruit or vegetation in abundance; fruitful; able
      to produce abundantly; prolific; fecund; productive; rich;
      inventive; as, fertile land or fields; a fertile mind or
      imagination.
      [1913 Webster]

            Though he in a fertile climate dwell. --Shak.
      [1913 Webster]

   2. (Bot.)
      (a) Capable of producing fruit; fruit-bearing; as, fertile
          flowers.
      (b) Containing pollen; -- said of anthers.
          [1913 Webster]

   3. produced in abundance; plenteous; ample.
      [1913 Webster]

            Henceforth, my early care . . .
            Shall tend thee, and the fertile burden ease
            Of thy full branches.                 --Milton.

   Syn: Fertile, Fruitful.

   Usage: Fertile implies the inherent power of production;
          fruitful, the act. The prairies of the West are
          fertile by nature, and are turned by cultivation into
          fruitful fields. The same distinction prevails when
          these words are used figuratively. A man of fertile
          genius has by nature great readiness of invention; one
          whose mind is fruitful has resources of thought and a
          readiness of application which enable him to think and
          act effectively.
          [1913 Webster]

WordNet (r) 3.0 (2006):

fertile
    adj 1: capable of reproducing [ant: infertile, sterile,
           unfertile]
    2: intellectually productive; "a prolific writer"; "a fecund
       imagination" [syn: fecund, fertile, prolific]
    3: bearing in abundance especially offspring; "flying foxes are
       extremely prolific"; "a prolific pear tree" [syn: prolific,
       fertile]
    4: marked by great fruitfulness; "fertile farmland"; "a fat
       land"; "a productive vineyard"; "rich soil" [syn: fat,
       fertile, productive, rich]

Moby Thesaurus II by Grady Ward, 1.0:

90 Moby Thesaurus words for "fertile":
   abounding, abundant, affluent, all-sufficing, ample, aplenty,
   blooming, bottomless, bounteous, bountiful, bursting, bursting out,
   conceptive, conceptual, copious, creative, diffuse, effuse,
   epidemic, esemplastic, exhaustless, extravagant, exuberant, fat,
   fecund, flourishing, flush, fructiferous, fructuous, fruitful,
   full, galore, generative, generous, germinal, ideational, ideative,
   imaginative, in plenty, in quantity, inexhaustible, ingenious,
   inspired, inventive, lavish, liberal, lush, luxuriant, many,
   maximal, much, notional, numerous, opulent, original, originative,
   overflowing, plenitudinous, plenteous, plentiful, plenty, pregnant,
   prevailing, prevalent, prodigal, productive, profuse, profusive,
   proliferous, prolific, rampant, replete, rich, rife, riotous,
   running over, seminal, shaping, superabundant, swarming, teeming,
   thriving, uberous, visioned, wealthy, well-found, well-furnished,
   well-provided, well-stocked, wholesale



U.S. Gazetteer Places (2000):

Fertile, IA -- U.S. city in Iowa
   Population (2000):    360
   Housing Units (2000): 161
   Land area (2000):     0.940131 sq. miles (2.434927 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.940131 sq. miles (2.434927 sq. km)
   FIPS code:            27390
   Located within:       Iowa (IA), FIPS 19
   Location:             43.264704 N, 93.421176 W
   ZIP Codes (1990):     50434
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Fertile, IA
    Fertile


U.S. Gazetteer Places (2000):

Fertile, MN -- U.S. city in Minnesota
   Population (2000):    893
   Housing Units (2000): 433
   Land area (2000):     1.892536 sq. miles (4.901645 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    1.892536 sq. miles (4.901645 sq. km)
   FIPS code:            20978
   Located within:       Minnesota (MN), FIPS 27
   Location:             47.533529 N, 96.283303 W
   ZIP Codes (1990):     56540
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Fertile, MN
    Fertile